4,4'-thio-bis-(dialkylphenol)/formaldehyde condensates
CA 1049044 A · Owner: Ruhrchemie Aktiengesellschaft · Inventors: Birnkraut, Hans-Walter; Kluy, Werner; Lutze, Siegfried
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A phenol/formaldehyde condensation product of a 4,4' -thio-bis-(dialkylphenol) and formaldehyde having a molecular weight of 1,000 to 4,000; a process for preparing such a condensation product by contacting 4 4' -thio-, bis- (dialkylphenol) and a source of formaldehyde in the presence of a protonic acid catalyst. Such condensation products are useful as antioxidants in olefin polymer or copolymer compositions.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted February 20, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 20, 1996.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.